1. Technical Field
The present invention relates to a projection system and a projector.
2. Related Art
A projector which can easily display large-screen images has been used in a broad application field such as a projection device for presentation, movie, and the like. Recently, resolution of an image input device such as a digital camera has been increasing, which can produce extremely fine images. However, resolution of a projector as an image output device for displaying the images produced by such an image input device having high resolution is lower than the resolution of the digital camera or the like. Moreover, according to a projector using liquid crystals as light modulation elements, the response speed of liquid crystals is relatively low, and thus visual recognizability of dynamic images needs to be improved.
Various technologies for overcoming these problems have been proposed (for example, see JP-A-10-304284 and JP-A-2006-203615). According to the method disclosed in JP-A-10-304284 (hereinafter referred to as first related art), highly fine image display can be achieved by shifting pixels on two images projected on a screen, that is, by so-called pixel shifting.
According to the method disclosed in JP-A-2006-203615 (hereinafter referred to as second related art), which is a technology for improving the visual recognizability of dynamic images, the visual recognizability can be increased by shifting the display timing of two projection images at the time of stack projection of projection image from plural projectors on a screen, that is, so-called synchronization shifting. Moreover, in the second related art, an intermediate image is produced based on image data to be displayed, and synchronization shifting is performed for the produced intermediate image by at least one of the plural projectors before projection. Thus, the visual recognizability of dynamic images improves.
According to the first related art, highly fine images can be displayed on the screen by performing pixel shifting for plural images. In the first related art, however, no consideration is given to improvement of visual recognizability of dynamic images. Thus, the problem of low visual recognizability of dynamic images cannot be solved.
On the other hand, the visual recognizability of dynamic images can be enhanced by synchronization shifting of the projection images projected by two projectors in the second related art. However, increase in the degree of fineness of images is not specifically considered, and thus no improvement over the fineness of image display can be achieved.
Which of pixel shifting and synchronization shifting is an appropriate method differs depending on the contents to be projected. For example, in case of still images, finer image display is typically desired. In case of dynamic images, highly recognizable dynamic display is typically desirable. It is therefore important to select pixel shifting or synchronization shifting according to the contents. In the first and second related arts, however, processing according to the contents is difficult.